Aspects of the present disclosure relate generally to wireless communications, and more particularly, to techniques for interference mitigation in unlicensed spectrum.
Wireless communication networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources. Examples of such multiple-access networks include Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA) networks.
A wireless communication network may include a number of evolved nodeBs (eNodeBs) that can support communication for a number of user equipments (UEs). A UE may communicate with an eNodeB via the downlink and uplink. The downlink (or forward link) refers to the communication link from the eNodeB to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the eNodeB.
To supplement conventional base stations, additional restricted power or restricted coverage base stations, referred to as small coverage base stations or cells, can be deployed to provide more robust wireless coverage to mobile devices. For example, wireless relay stations and low power base stations (e.g., which can be commonly referred to as Home NodeBs or Home eNodeBs, or referred to as femto cells, pico cells, etc.) can be deployed for incremental capacity growth, richer user experience, in-building or other specific geographic coverage, and/or the like. Such low power or small coverage (e.g., relative to macro network base stations or cells) base stations can be connected to the Internet via broadband connection (e.g., digital subscriber line (DSL) router, cable or other modem, etc.), which can provide the backhaul link to the mobile operator's network. Thus, for example, the small coverage base stations can be deployed in user homes to provide mobile network access to one or more devices via the broadband connection. Because deployment of such base stations is unplanned, low power base stations can interfere with one another where multiple stations are deployed within a close vicinity of one another.
Operation of wireless devices in certain portions of a shared or unlicensed spectrum may experience interference from another radio access technology (RAT) using the spectrum. For example, both long term evolution (LTE) and Wi-Fi may operate in an unlicensed 5 GHz band. Interference from the second RAT on a signal of the first RAT may degrade the signal quality of the first RAT. In view of the foregoing, it may be understood that mitigation of interference in shared spectrum is desirable.